This invention pertains to the recovery of pharmaceutical substances and, in particular, to the recovery of pharmaceutical substances carried in two component, hard gelatin capsules.
In the manufacture of encapsulated pharmaceuticals, a certain number of capsules are rejected for one reason or another during the manufacturing process. As the number of rejected capsules grows and the cost of the encapsulated pharmaceutical increases, it becomes increasingly important to recover the pharmaceutical product from the rejected capsules. In order for the recovery process to be acceptable, however, it must be carried out such that the physical integrity--bulk density, particle size, etc.--of the pharmaceutical product is not significantly altered.
Prior art procedures for the recovery of encapsulated pharmaceuticals have been mainly directed to the recovery of pharmaceutical product in powdered form. One practice presently employed is to subject the capsules to a milling procedure wherein the capsules are ground to produce a mixture of hard capsule fragments and powdered pharmaceutical. The mixture is then screened to separate the capsule fragments from the powdered pharmaceutical.
Another procedure which has been proposed for the recovery of pharmaceutical powder is disclosed in U.S. Pat. No. 3,800,399. In this procedure a pressure differential is created between the capsule interior and the surrounding area. This pressure differential causes separation of the capsule cap from the capsule body or rupturing of the capsule in cases wherein the cap and body are tightly fastened. Removal of the pharmaceutical powder is then carried out by blowing same through a screen which inhibits passage of the capsules.
In present day pharmaceuticals, it is often the case that the encapsulated product is in pellet or bead form, rather than in powdered form. Recovery of such pharmaceutical beads using the prior milling procedure is, however, undesirable, as the grinding action of this procedure is detrimental to bead integrity. Furthermore, present day capsules are usually provided with a strong locking mechanism. Use of the pressure differential procedure would thus require a high pressure to break this locking mechanism which again could be detrimental to bead integrity.
Additionally, it is usually the case that expensive filling equipment has been employed to fill the capsules. Use of further specialized milling or pressurizing equipment to recover the pharmaceutical product adds to this expense and, furthermore, reduces any gains achieved by the recovery.
It would thus be advantageous if a recovery procedure could be developed for both bead filled and powder filled capsules. It would be further advantageous if a procedure could be developed which could make use of some or all of the existing filling equipment.
It is therefore an object of the present invention to provide a method and apparatus for the recovery of encapsulated pharmaceutical product.
It is also an object of the present invention to provide a method and apparatus for the recovery of encapsulated pharmaceutical product which is adaptable to present capsule filling equipment.
It is further object of the present invention to provide a method and apparatus for the recovery of pharmaceutical beads in a manner which substantially preserves bead integrity.